Hi all, Just wanted to ask regarding this JK Rowling signature on a Philosopher's Stone book (30th print) I had bought last year. Any opinions regarding its veracity?

I know the JK Rowling signature is faked a lot, and there is no certificate of authenticity with this signature. The signature is on the same book as three other signatures from three actors: Alan Rickman, Bonnie Wright and Daniel Radcliffe. The signatures are allegedly all from the same night - the night of the London premiere of the Half Blood Prince.  Thank you all for your time and assistance!